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The Sedimentary Record The Greatest Volcanic Ash Falls in the Phanerozoic: Trans-Atlantic Relations of the Ordovician Millbrig and Kinnekulle K-Bentonites Stig M. Bergström, Department of Geological Sciences, The Ohio State University, Columbus, OH 4321; [email protected] Warren D. Huff, Department of Geology, University of Cincinnati, Cincinnati, OH 45221; [email protected] Matthew R. Saltzman, Department of Geological Sciences, The Ohio State University, Columbus, OH 43210; [email protected] Dennis R. Kolata, Illinois State Geological Survey, 615 E. Peabody Dr., Champaign, IL 61820; [email protected] Stephen A. Leslie, Department of Science, University of Arkansas at Little Rock, Little Rock, AR 72204; [email protected]

Figure 1: Outcrop of the Millbrig K-bentonite ABSTRACT along U.S. Highway 68 at entrance to Beds of altered volcanic ash (K-bentonites) are often widespread geographically, but they Shakerstown, Kentucky. The ash bed is about generally occur sporadically in the lower Paleozoic geologic record. Most occurrences 70 cm thick at this section. Head of top have been recorded from , northern , and Argentina.These ash hammer marks the base of the bed. beds are in most cases less than 20 cm thick but three exceptional beds in the Ordovician, the Deicke and Millbrig in North America and the Kinnekulle in northern ticularly thick beds, the Deicke and the Europe, reach thicknesses of 1-2 m or more and can be traced over millions of km2. Each Millbrig K-bentonites (Figure 1), which have has an estimated dense rock equivalent volume of around 1000 km3 or more, and they been traced over most of the eastern and cen- represent the largest Phanerozoic volcanic ash falls recorded.Various lines of evidence, tral part of the (Huff and Kolata, particularly biostratigraphic and chemostratigraphic, indicate no significant age difference 1990; Kolata et al., 1996; Fig. 2). In northern between the Millbrig and Kinnekulle beds but whether or not these originated from the Europe, there is one especially prominent ash same gigantic eruption(s) is still speculative.At any rate, these ultraplinian eruptions bed, the Kinnekulle K-bentonite, which has appear to have been derived from a volcanic arc or microplate subduction zone along the been identified across and the eastern side of Laurentia. In view of their enormous size and continent-wide distribution, and locally in Great Britain it is surprising that these ash beds are not directly associated with any notable faunal (Bergström et al., 1995). The Millbrig, extinction event or any significant lithologic change in the sedimentary record. Deicke, and the Kinnekulle are locally 1-2 m or more thick and before compaction, they apparently represented ash layers with an orig- INTRODUCTION beds are apparently rare but more than 60 inal thickness of at least four times that figure. In terms of destruction of land and life, vol- such beds have been recorded from the The Millbrig covers an estimated area of at canic eruptions surely rank as some of our Ordovician of North America and more than least 2.2x106 km2 in North America and the planet’s most severe catastrophes. In the time 150 from Baltoscandia (Kolata et al., 1996). Kinnekulle at least 6.9x105 km2 in northwest- interval of human history, some such erup- Although Silurian (Bergström et al., 1998; ern Europe. In terms of dense rock equiva- tions have been especially devastating, perhaps Huff et al., 2000) and Devonian (Ver lent, the silicic magma is estimated to have the most well-known one being the Vesuvius Straeten, 2004) K-bentonites have been been 1509 km3 for the Millbrig and 972 km3 eruption in 79AD. As vividly reconstructed in recorded from several , such ash beds for the Kinnekulle (Huff et al., 1996). These Robert Harris’ (2003) fascinating novel appear to be less common in those systems values do not include the vast quantity of vol- Pompeii, this disastrous eruption destroyed in than in the Ordovician. Interestingly, concen- canic ash presumably deposited in the Iapetus a couple of days the towns of Pompeii, trations of K-bentonites in the geologic record between Baltica and Laurentia and Herculaneum, and Stabiae and killed virtually appear to reflect collisional orogenic episodes, subsequently subducted. The truly gigantic all of their inhabitants. many of the Ordovician and Devonian ones size of these ash falls is indicated by the fact The presence of volcanic ash beds in many being coeval with the Taconic and Acadian that the dense rock equivalent of the 1980 geologic successions provides evidence of simi- orogenies, respectively. Mt. St. Helens eruption is estimated at 0.2 lar, but in many cases far greater, volcanic ash The thickest and most widespread km3 (Huff et al., 1992). These enormous ash eruptions in the Earth’s pre-human history. Paleozoic K-bentonites occur in the Middle falls are the largest recorded in the Earth’s The present account centers on beds of altered Ordovician Mohawkian Stage in North Phanerozoic history. volcanic ash, known as K-bentonites, in the America (Kolata et al., 1996) and in the Many aspects of the distribution, mineralo- lower Paleozoic of North America and north- Keilan Stage in Baltoscandia (Bergström et al., gy, bio- and chemostratigraphy, isotope geolo- ern Europe. In the Cambrian K-bentonite 1995). In North America, there are two par- gy, and the eventstratigraphic and paleogeo-

4 | December 2004 The Sedimentary Record increase from to southwestern and southern which indicates that the source of the ash was located southwest of Scandinavia. Both in North America and Baltoscandia, these thickness trends are associ- ated with a general increase in grain size toward the source area. According to Huff et al. (1996), the grain size and distribution patterns indicate that the ash originated from plinian and co-ignimbrite eruptions and that the pyro- clastic material was widely distributed by equa- torial stratospheric and tropospheric winds. Plotted on widely used paleogeographic recon- structions, the distribution patterns of the Millbrig and Kinnekulle beds (Figure 3) are not in conflict with the idea that they had a com- mon source. Although interesting, these distri- bution patterns do not provide any conclusive Figure 2: Stratigraphic cross section from Minnesota to Alabama-Georgia showing the stratigraphic evidence of the direct source relationships of position of the Millbrig and Deicke K-bentonites. (Modified from Huff and Kolata, 1990.) these ash beds. graphic significance of these ash beds have DISTRIBUTION BIOSTRATIGRAPHY been investigated, particularly during the last As noted above, the Millbrig has been identi- Of crucial importance for clarifying the rela- two decades (see, e.g., Kolata et al., 1996). fied over much of eastern and central North tionships between the Millbrig and One interesting problem that has attracted America, from the Mississippi and Kinnekulle beds is obviously to be able to special attention and some recent controversy Oklahoma to the Appalachians (Kolata et al., demonstrate that they are of the same age. is whether the Millbrig and the Kinnekulle 1996; Figure 2). A maximum thickness map Possible methods for this include biostratigra- beds are equivalent and may represent the produced by Huff et al. (1996; Figure 3) shows phy and radiometric dating but both these same colossal eruption. If that was the case, a gradual increase in thickness from a few cm approaches have their special problems. the combined dense rock equivalent of these in the Mississippi Valley to 1-2 m in the south- Fortunately, both the Millbrig and the beds would be on the order of 2500 km3. Such eastern portion of the continent suggesting that Kinnekulle beds occur in successions contain- an eruption ought to have had profound cli- the source volcano(es) of the ash was located ing biostratigraphically highly diagnostic fos- matic and biological effects on a global scale. off the southeastern part of the continent (pres- sils such as graptolites and conodonts. In In the present contribution, we summarize ent-day coordinates). A similar map of thick- North America, e.g. in the section at various types of data that bear on the consan- ness trends of the Kinnekulle bed (Huff et al., Strasburg, Virginia (Finney et al., 1996), the guinity of these extraordinary ash beds. 1996; Figure 3) shows a marked thickness Millbrig is associated with graptolites of the

Iapetus Ocean

Figure 3: Sketch map of central and eastern USA and Baltoscandia showing study localities (dots) and thickness trends (cm) of the K-Bentonite Source? Millbrig and Kinnekulle 20010080 6040 K-bentonites, respectively. 3 10 (Modified after Huff et 20 40 20 10 al., 1996.) The contours 100 140 are estimated based on 30˚ S 60 the thicknesses recorded at sites marked by dots. Contour estimates far away from data points 0 300 Km are less well constrained.

December 2004 | 5 The Sedimentary Record

NORTH AMERICA BALTOSCANDIA and in conflict with all biostratigaphic evi- RANGES CONODONT N. AM. K-BENTONITES dence. As shown by Goldman and Bergström K-BENTONITES ZONE OF KEY & GRAPTO- & 13 13 GRAPTO- (1997), the D. complanatus Zone corresponds LITE Z. ZONE STAGE C EXCURSION C EXCURSION LITE Z. MIDCONT. ATL. CONOD. LITES GRAPTO- to part of the Richmondian Stage of the G. Upper Ordovician in North America, an pygmaeus interval several stages above the position of Am. the Millbrig in the upper Middle Ordovician EDENIAN STAGE B. superbus confluens C. Chatfieldian Stage. spiniferus Am. superbus Am. 13 δ C carb. 13 δ C carb. CHEMOSTRATIGRAPHY 0 1 2 3 0 1 2 O. Extensive research in recent years (see, e.g., ruede- RAKVERIAN manni OAN- Ludvigson et al., 2004; Saltzman et al., 2003) DUAN 13 P. clingani have shown that a prominent δ C positive D. tenuis C. bicornis Climacograptus excursion is present in the early Chatfieldian americanus

CHATFIELDIAN stratigraphical interval just above the Millbrig Am. K-bentonite. This excursion was first recog- tvaerensis KEILAN Climacograptus spiniferus Climacograptus MILLBRIG KINNEKULLE nized in the Guttenberg Member of the P. K-BENTONITE K-BENTONITE

DEICKE undatus tvaerensis Am. Decorah Formation of Iowa (Hatch et al., C. K-BENTONITE bicornis 1987) and is now known as the GICE

foliaceus (Guttenberg Isotopic Carbon Excursion). It

01 2 D. has been identified not only over much of the TURINIAN HALJUAN eastern and central USA but also in the (Saltzman and Young, 2005) and has Figure 4: Biostratigraphic classification of the Millbrig and Kinnekulle K-bentonites, position of the proved to be of extraordinary value as a 13 13 GICE δ C excursion, and the stratigraphic ranges of some key graptolites. The North American δ C chemostratigraphic correlation tool. curve is from Lexington, Kentucky, and the Baltoscandic one from Fjäcka, Sweden (after Saltzman et al., 2003). Note that these different types of evidence strongly suggest that these K-bentonites occupy a Depending on the local magnitude of net closely similar, or the same, stratigraphic position. depositional rate, it begins 2-10 m above the Millbrig bed in most sections and ends below highest part of the C. bicornis Graptolite it has proved difficult to establish the precise the base of the A. superbus Conodont Zone. Zone, and at many other localities, such as at level of the top of the latter conodont zone Importantly, recent chemostratigraphic work Lexington, Kentucky, the Millbrig occurs in although it is evidently in the lower part of in Baltoscandia (Saltzman et al., 2003; Ainsaar the upper part of the North American the Moldå Formation (Saltzman et al., 2003) et al., 2004) has led to the discovery of a very P. undatus Conodont Zone (Richardson and at a level well above the Kinnekulle K-ben- similar, prominent δ13C excursion one to a few Bergström, 2003), at a level well below the tonite. It is concluded that based on the good m above the Kinnekulle bed. Apart from the top of the Atlantic A. tvaerensis Conodont stratigraphic resolution of these key index fos- latest Ordovician (Hirnantian) δ13C positive Zone (Saltzman et al., 2003; Figure 4). sil groups, there is no recognizable difference excursion, this is the most conspicuous such Hence, the biostratigraphic position is well in the biostratigraphic position of the excursion in the Middle and Upper established in terms of standard North Millbrig and the Kinnekulle beds (Figure 4). Ordovician of both North America and north- American zone units. Because of faunal It might be noted that the correlation of the ern Europe. Because many such excursions provincialism, different graptolite zones are Millbrig with a level in the lower Pirguan have been shown to have a global distribution, used in Baltoscandia and in North America Stage (D. complanatus Zone) of Baltoscandia there is little doubt that this Baltoscandian and the Kinnekulle bed is in the upper part of by Kaljo et al. (2004, fig. 5) is improbable excursion is the same as the North American the D. foliaceus (formerly multidens) Zone (Huff et al., 1992). Trans-Atlantic correlations 0F*5(*2548$55< are, however, facilitated by the fact that the &/$<721&2,2:$

P Baltoscandic succession contains some North ',&.(<9,//(1257+  *5$17&2:,6&216,1 American zone index graptolites such as )-b&.$6287+ 5,67,.h/$ &(175$/6:('(1 6287+(51(6721,$ Climacograptus bicornis and Climacograptus P  ,RQ0EU P 1DEDOD  spiniferus. Similar to its range above the ,RQ0EU 6WDJH   P  'LFNH\YLOOH  5DNY Millbrig in the USA, the former ranges strati-  

.E "'LFNH\YLOOH =RQH 2DQGX 6WDJH .E 

 ENUIS graphically up to somewhat above the T 

 '(&25$+)250$7,21 

Kinnekulle bed, and as in North America, *XWWHQEHUJ0EU *XWWHQEHUJ0EU (ONSRUW.E  (ONSRUW.E   .HLOD6WDJH =RQH

C. spiniferus appears slightly higher than the '(&25$+)250$7,21  .LQQH

0LOOEULJ.E 6SHFKWV  6SHFKWV .LQQHNXOOH )HUU\0EU 0LOOEULJ.E  )HUU\0EU NXOOH disappearance of C. bicornis. Hence, in terms  UNDATUS 'HLFNH.E 'HLFNH.E .E .E 6WDJH

 +DOMDOD )P YLOOH  'DOE\)P 6NDJHQ)P 0ROGn)P )P of graptolite biostratigraphy, the Kinnekulle YLOOH 3ODWWH 3ODWWH         bed occupies a closely similar position to the             D&FDUE  Millbrig bed. The Kinnekulle bed is just D&FDUE D&FDUE D&FDUE above the top of the B. alobatus Subzone of Figure 5: Comparison of the GICE carbon isotope excursion at some North American and the A. tvaerensis Conodont Zone (Saltzman et Baltoscandian localities and its relation to the Millbrig and Kinnekulle K-bentonites, respectively. See al., 2003) but because of biofacies differences, Ludvigson et al. (2000) for data in Iowa and Wisconsin. See Ainsaar et al. (2004) for Estonia data.

6 | December 2004 The Sedimentary Record

 PALEOGEOGRAPHY Geochemical studies of the trace elements of  the Millbrig and Kinnekulle beds (Huff et al., 1992; 1996; Bergström et al., 1995) indicate  that their source volcano(es) was associated with an active subduction zone, possibly along  an island arc or a microplate. Because the western side of Baltica is thought to have been

H20J2  a passive margin, Huff et al. (1996) considered ) it more likely that the source of the volcanic

 ash was located on the North American side of the Iapetus Ocean (Figure 3), possibly a region

 such as the Oliverian Terrane (McKerrow et .LQQHNXOOH al., 1991). Although such a position of the 0LOOEULJ source volcano(es) is in general agreement  'HLFNH with the distribution patterns of the Millbrig and Kinnekulle volcanic ashes, no potential  source volcano(es) has been identified and the 7L2  ZW  precise location of the ash eruption site(s) remains speculative. It is quite possible that Figure 6: Bivariate plot of TiO2 vs. FeO/MgO from more than 800 biotite analyses from the Deicke, Millbrig, and the Kinnekulle K-bentonites. Note that most of the Deicke samples plot separately whereas this volcanic source region subsequently was those of the Kinnekulle and Millbrig show considerable overlap suggesting that the Deicke bed is a single subducted. event deposit whereas the two other beds represent more than one eruptive event (from Huff et al., 2004). CONCLUSIONS GICE (Saltzman et al., 2003; Ainsaar et al., be the record of separate eruptions. Clearly, A review bearing on the consanguinity of the 2004). The very close similarity in stratigraph- the compositional variations through these ash these two giant ash falls shows that based on ic position of the GICE to the Millbrig and beds are more complex than suggested by pre- biostratigraphy and chemostratigraphy, they are Kinnekulle beds (Figure 5) provides powerful vious work and their relations to different closely similar, if not identical, in age. At least chemostratigraphic evidence of the coeval eruptions and perhaps different eruptive cen- parts of these huge ash deposits are also indis- nature of these ash beds. ters need further study. tinguishable chemically and their geographic distribution patterns are in agreement with the GEOCHEMISTRY RADIOMETRIC DATING idea that they originated from the same region Recent comprehensive studies have shown During the last 50 years, about a dozen differ- and even shared the same source volcano(es). that chemically, including both major and ent isotopic age dates have been published for Radiometric datings are considered inconclu- trace elements, the Millbrig and Kinnekulle each of the Millbrig and the Kinnekulle beds. sive regarding the possible age equivalence of K-bentonites are quite similar (Huff et al., They show a considerable spread (more than the Millbrig and Kinnekulle beds. Regardless of 1992, 1996; Kolata et al., 1996). Chemical 10 million years for each bed) which at least whether the ash accumulations represented the fingerprinting methods have been used to partly reflects the use of different isotopic same eruptions, or separate eruptions closely identify the Millbrig regionally in North methods. However, there is no obvious trend spaced in time, the formation of these deposits America (Kolata et al., 1987; Mitchell et al., toward concentration of even the recent dat- represent mega-catastrophic events of a unique 2004) and corresponding work has been car- ings to more precise isotopic ages. The prob- magnitude in the Earth’s Phanerozoic history. ried out on the Kinnekulle bed in Sweden and lems with dating these ash beds are illustrated In view of this, it is highly notable that the rock Estonia (Bergström et al., 1995; Kiipli et al., by the data in Min et al. (2001) who, using record shows no relation to any marked climat- 2004). In a study of the chemistry of volcani- the 40Ar/39Ar method, not only found an age ic effects and to any general extinction event in cally generated biotite phenocrysts from the difference of about 7 m.y. between the the marine faunas as one would expect from Millbrig and the Kinnekulle beds, Haynes et Millbrig and the Kinnekulle but also dated the such a large-scale catastrophe. al. (1995) recognized a difference between Millbrig as being about 447 Ma. In terms of these ash beds in terms of their content of recently published time scales (e.g., Webby et ACKNOWLEDGMENTS

FeO, MgO, Al2O3, MnO, and TiO2 that they al., 2004) the latter date would place the The present research was supported by NSF interpreted as indicating separate eruptive Millbrig high up in the Upper Ordovician grants EAR-9005333, 9204893, 9004559, events. Recent more comprehensive studies (Richmondian) which, as indicated above, is and 9205981. We are indebted to John (Huff et al., 2004; in review) show that both in drastic conflict with biostratigraphic and Repetski and Dan Goldman for reading the Millbrig and Kinnekulle include multiple ash chemostratigraphic data, as well as with other manuscript and offering useful comments. beds that apparently represent separate, in isotopic dates for this bed. Accordingly, we time very closely spaced, eruptions. In terms conclude that the precision of current radio- REFERENCES AINSAAR, L., MEIDLA, T., and MARTMA, T., 2004, The Middle of chemical composition, some of these layers metric datings is currently not good enough to Caradoc facies and faunal turnover in the Late Ordovician Baltoscandian palaeobasin: Palaeogeography, Palaeoclimatology, in the Millbrig and the Kinnekulle are indis- successfully assess whether or not the Millbrig Palaeoecology, v. 210, p. 119-133. tinguishable (Figure 6) and they may be the and the Kinnekulle beds are equivalent. BERGSTRÖM, S.M., 1995, HUFF, W.D., KOLATA, D.R. and BAUERT, H., 1995, Nomenclature, stratigraphy, chemical finger- products of the same eruption(s). Other layers printing, and areal distribution of some Middle Ordovicain K-ben- are compositionally slightly different and may tonites in Baltoscandia: GFF, v. 117, p. 1-13.

December 2004 | 7 The Sedimentary Record BERGSTRÖM, S.M., HUFF, W.D., and KOLATA, D.R., 1998, Early HUFF, W.D., KOLATA, D.R., BERGSTRÖM, S.M., and ZHANG, Y-S., McKERROW, W.S., DEWEY, J.F., and SCOTESE, C.R., 1991, The Silurian (Llandoverian) K-bentonites discovered in the southern 1996, Large-magnitude Middle Ordovician volcanic ash falls in Ordovician and Silurian development of the Iapetus Ocean. Special Appalachian thrust belts, eastern USA: Stratigraphy, geochemistry, North America and Europe: dimensions, emplacement and post- Papers in Palaeontology, v. 44, p. 165-178. and tectonomagmatic and paleogeographic implications: GFF, v. 120, emplacement characteristics: Journal of Volcanology and Geothermal MIN, K., RENNE, P.R., and HUFF, W.D., 2001, 40Ar/39Ar dating of p. 149-158. Research, v. 73, p. 285-301. 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Isotopic and sequence stratigraphic evidence Gigantic Ordovician volcanic ash falls in North America and Europe: Ordovician (Turinian-Chatfieldian) carbon isotope excursions and their from western Laurentia: Geology, in press. Biological, tectonomagmatic, and event-stratigraphic significance: stratigraphic and palaeoceanographic significance: Palaeogeography, VER STRAETEN, C., 2004, K-bentonites, volcanic ash preservation, Geology, v. 20, p. 875-878. Palaeoclimatology, Palaeoecology, v. 210, p. 187-214. and implications for Early to Middle Devonian volcanism in the HUFF, W.D., BERGSTRÖM, S.M., and KOLATA, D.R., 2000, Silurian LUDVIGSON, G.A., WITZKE, B.J., SCHNEIDER, C.L., SMITH, Acadian orogen, eastern North America: Geological Society of K-bentonites of the Dnestr Basin, Podolia, Ukraine: Journal of the E.A., EMERSON, N.R., CARPENTER, S.J., AND GONZALEZ, America Bulletin, v. 116, p. 474-489. Geological Society, London, v. 157, p. 493-504. L.A., 2000, A profile of the mid-Caradoc (Ordovician) carbon iso- WEBBY, B.D., COOPER, R., BERGSTRÖM, S.M., and PARIS, F., HUFF, W.D., and KOLATA, D.R., 1990, Correlation of the Ordovician tope excursion at the McGregor Quarry, Clayton County, Iowa: 2004, Stratigraphic framework and time slices. In Webby, B.D., Paris, Deicke andMillbrig K-bentonites between Mississippi Valley and the Geological Society of Iowa Guidebook, v. 70, p. 25-31. F., Droser, M.L., and Percival, I.G., 2004 (eds.). The Great Ordovician Southern Appalachians: AAPG Bulletin, v. 74, p. 1736-1747. biodiversification event. Columbia University Press, p. 41-47. PRESIDENT’S OBSERVATIONS

with members and officers of our Society. SEPM MEMBERS: Potential venues for increased engagement include broadening our sponsorships to focus AN INTERNATIONAL COMMUNITY on meeting sessions and research topics where we have common interests with IAS; and part- SEPM is an international society, committed Brazil, Columbia, Ecuador, Peru, and nering with AAPG in their international meet- to being a leader in the global sedimentary Venezuela. Our members come ings. To test new ideas and emerging concepts geology community. We have members in from throughout the region including Iran, in our field and facilitate scientific exchange, many countries and the majority of our new Iraq, the Gulf States, Saudi Arabia, Jordan, SEPM could also co-sponsor field seminars to members are international. Currently, 35% of and Turkey. Our Society truly does connect a classic field areas around the globe. We could our total membership (1328 of 3752) come global community. encourage and sponsor new regional sections from outside the U.S. These members are dis- SEPM’s mission as a Society is to exchange that would allow increased participation by tributed around the globe and occupy every and disseminate knowledge in Sedimentary our international members. We currently have continent except Antarctica, although I am Geology. Our primary means to do this are international sections in , and sure we have temporary residents there during our meetings, research conferences, and publi- . Other regions with a critical the summer field season. Members in North cations. Meetings and conferences are con- mass of members include Japan, and - America reside in the U. S., , , ducted in partnership and collaboration with . Perhaps we should also think and the . Our African members AAPG, GSA, and the IAS. Our partnership about defining and electing regional interna- occupy the length and breadth of that conti- with AAPG, is a particular focus, and involves tional counselors. Possible regions are Austral- nent, from Algeria, Morocco, and Egypt in the contributing our expertise at the annual meet- , Europe/, and the Middle East. In north to Namibia and South Africa in the ing, as presenters at technical sessions, spon- addition, we could include in the Sedimentary south, to Nigeria and Ghana on the west, and sors and leaders of technical sessions, short Record, news from around the world on in the east. We have 661 European courses, and field trips. Our publications con- advances in our science, and updates on members representing almost every nation in tinue to enjoy strong support around the upcoming research conferences. This would that region, including Austria, Belgium, world, and our research conferences target enhance communication among our members Croatia, Czech Republic, , , leading edge topics across the wide range of and ensure that our science is spread widely France, Germany, Great Britain, Greece, our discipline. Although our efforts to fulfill around the globe. All of the above are just a Hungary, Ireland, Italy, Netherlands, Norway, our mission draw on a variety of venues, number of possible ideas for advancing our Poland, Portugal, Romania, Russia, Slovakia, Sedimentary Geology is a global science, and mission. We will be discussing our interna- Slovenia, Spain, Sweden, and Switzerland. we must increase our efforts to engage the tional strategy at our fall Council Meeting at Our Asia contingent is 217 strong and reside international community. We must include, in the GSA meeting in Denver. I’d like to hear from India on the west, to Japan on the east, more direct ways, the wealth of talent and sci- from you, the members. Let me know you’re to Australia and New Zealand in the south, ence of our global membership. ideas, and I hope to see many of you in and include representatives from Brunei, It seems evident that SEPM needs to Denver. Indonesia, Malaysia, , Singapore, increase participation in international confer- Sri Lanka, Taiwan, and Thailand. South ences and meetings. Let me throw out some Rick Sarg, President SEPM America includes members from Argentina, ideas that I have been gathering in discussions [email protected]

8 | December 2004